Process for cracking coal and oil



`lune 15 1926.

w. E. TRENT PRocEss FOR CRACKIN'G COAL AND OIL Filed Sept. 27, 1924 Patented .lune 15, 192.6. j

UNITED STATES WALTER EDWIN TRENT, OF vWASHllll'tirloll, DISTRICT 0F COLUMBIA 1,589,023 PATENT- OFFICE.

PROCESS FOR CRCKING COAL AND OIL.

Application led September 27, 1924. Serial lfo'. 740,385.`

The invention relates to improvements in processes for the production of purified solid fuels in conjunction with the production of liquid motor fuels.

The purified solid fuel is made by amalgamating finely pulverized coal with an oil residuum obtained .by first evaporating the lighter boiling fractions from a crude or fuel oil.

The heat for evaporating these lighter fractions is generated by the isothermic compression of the evaporated vapors and then imparting this heat to the original oil through the medium of a heat exchanger.

It is necessary to use a residuum with a highpercentage of asphalt or carbon so that the resulting'amalgam of the coal particles and residuum, when baked or carbonized,

' will provide the binder for making hard,

strong fuel masses.

It is `not the intention to use a residu-um that will make hard and strong fuel masses in a green state by merely briquetting or shaping and then cooling. They are only to be so after baking and carbonizing and the residuum is to be such that from about 40 to 80% of same Will vaporize under the baking Vor carbonizing treatment. These va- .porized fractions are conducted to and mixed with the evaporated fractions derived from the original charging stock that enters the heat exchanger and simultaneously compressed, then cooled and liquefied by circulating through the heat exchanger in tubes surrounded by the oil to be evaporated.

The positive displacement compression of these vapors is to develop the combination of pressure and temperature that causes the maximum degree of cracking of the vapors into lighter boiling fractions and the heat of compression so generated is to be transferred to and cause the vaporization of the ori inal oil. llhe com ressed vapors constitute, when condense a pressure distillate from which is to bet extracted and refined the desired fractions of liquid motor fuel by any of the existing methods, and the remaining fractions are to be added to the residuum from the heat exchanger or to the original charging stock to undergo the treatment cycle a second time.

- The invention particularly relates to a process broadly described in my Patent N o. 1,420,165 relating to the purification of coals by amalgamation with oils obtained by the distillation of the product and aims to carry out the operation with the greatest possible heat efficiency and economy and further to produce definite quality forms of both solid and liquid fuels.

The heat utilization is practiced by using A boiler and steam actuated compressor, the pressure steam to actuate the oil vapor compressor, the exhaust steam from the compressor to be utilized to heat the Water used in the amalgamator box. The boiler stack gases are used to heat the amalgam baking apparatus. The heat generated by oil vapor compression is to be utilized to vaporize the original charging vstock oil; to utilize the heat in the vaporized oil fractions leaving the baking apparatus by subjecting same While in vapor form to cracking pressure and temperature, the utilization of the sensible heat of the oil residuum to make amalgam.

An alternative operation, Without departing from the medium emboding efcient heat utilization, is to use an internalcombustion engine as the prime mover, instead of a boiler and steam'drivenvapor compressor, to operate the oil vapor compressor. The Waste jacket heat of the engine, which is about 50% of the total original heat of the fuel oil, Will be utilized to heat both the amalgamating Water and the original .lcharging stock oil divided as to give the highest efficiency. The exhaustk gases of the engine will be utilized to heat the baking oven.

In the drawings I have shown diagrammatically an apparatus for supporting this process.

Referring now more particularly to the drawings wherein like reference characters indicate corresponding parts, the numeral l designates an amalgamator in which finely pulverized coal of say 100 meshes to the linear inch is introduced, preferably in Water suspension, through the feeding line. rlhis amalgamator contains a series of agitators for thoroughly a'gitating the material therein. 'llo this amalgamator l also introduce liquid hydrocarbon residuum oils, which oils are delivered hot after having had the lighter fractions removed by evaporation.

Exhaust steam is introduced to this amall' to the amalgamator in a Wayto be hereinafter described. t

rlhe material undergoing amalgamation in the amalgamator is such as describedin my patent aforesaid, and when discharged from the amalgamator consists of plastic mixtures of coal and oil of a consistency resembling putty, usually in the form of spherical bodies of desired diameters. These bodies, 0r masses, are largely free of water and detached ash. 'lhey are deposited on the screen 6 so as to be separated from water and ash, and this screen carries them to a hopper 7, there to be formed or moulded into desired shapes and conveyed through an elongated baking oven 8, which is heated by smoke stack gases from the steam boiler. The purpose for baking or carbonizing the formed fuel masses is to make them hard and strong so they may be transported, and handled, to make them smokeless under combustion, or substantially so, to remove the oils vaporized at the temperatures employed and to convert them into light boiling motor fuel fractions. n

Adverting now to the steam boiler, it will be seen that the steam from this boiler discharges through a line 10 to a compressor cylinder 11, being exhausted from this cylinder through a line 12 into the amalgamator 1. Hot boiler gases from the boiler also discharge through the line 13 into the baking oven 8 to supply the necessary heat to this oven to bake or carbonize the material passing therethrough. Suitable valves are provided for controlling the passage of the heating gases through these lines.

It will be observed that the steam from the boiler 5 first passes to the steam compressor cylinder 11. This steam is there utilized to operate a compressor 14: employed for the purpose of subjecting hydrocarbon vapors to a high degreeof compression to crack said vapors. The steam exhausting from the power compressor cylinder 11 then asses to the amalgamator. In the process described crude oil, or other charging stock, is fed from a tank 15 passing therefrom throu h a line 16 from Where a portion of the o1 can pass through a line 17 to the jacket 18 of the vapor compressing cylinder to control the temperature of compression in said c linder while the major part of the oil supp y passes through the line 19 to a space 20 in the elongated heat exchanger 21. That part of the oil passing through the jacket of the vapor compressing cylinder also enters the space 20 through the line 22 in a somewhat preheated condition. In the space 20 of the heat exchanger there are a plurality of tubes 23 receiving the com pressed vapors, by means of which the heat of the cracked vapors is indirectly imparted to the charging stock in a manner now to be described.

A A substantial part of the liquid charging stock entering the space 20 is vaporized, the vapors passing from this space thrqugh the line 25 to the compressor let where said vapors are subjected to an exceedingly high stage of compression, this exothermic coinpression raising the temperature of the vapors to a cracking condition of temperature and pressure so that they vundergo substantial conversion in said compressor. The cracked vapors-from the compressor while at a cracking temperature, discharge threugh the line 27 into the tubes 23 passing through the interior of the heat exchanger. These hot vapors serve to vaporize substantial portions of the incoming charging stock to provide the vapors that are to enter the compressor 14. The vapors by being robbed of their heat largely condense in the tubes 23 and the condensate flows out through the line 28 into the receiver 29 employed for collecting the converted products. rlhe space 20 of the heat interchanger is preferably maintained under a vacuum so as to lower the vaporizing point of the incoming cliarging stock. The unvaporized oil from this chamber consisting of large quantities of heavy oils, tar, pitch, carbon, etc., is continuously withdrawn through the line 30 and collected in a receiver 31 from where it is conveyed by the line 32 directly to the amalgamator 1. It will also be understood that the amalgamated product passing through the baking oven 8 is subjected to a temperature of say 550O F., to 1,000o F., and that the volatiles contained in both the coal and the oil constituting this amalgamated product are vaporized either in part or to any degree desired depending on temperature, time of treatment and type of solid product wanted, these vapors passing through the line 33 to the line 25 for passage on to the compressor 26 to undergo cracking by reason of the high temperature and pressure they attain due to the high compression of these vapors.

As an illustration of an operation, coal of a bituminous character, preferably of a lineness of 100 meshes per linear inch, is introduced in water suspension to the amalgamator, and there mixed with a liquid hydrocarbon residue containing substantial quantities of carbon base. The quantity of hydrocarbon material used is approximately in the proportion of one part hydrocarbon material to tive parts coal by weight. The amalgamated material is deposited on the screen 6 and after being formed into masses of uniform size, is then introduced to the baking oven 8 which is heated by furnace gases passing through the line 13. rlhis oven is maintained at a temperature of say 050 to 700 F., causing a vaporization of the lighter volatiles contained in the oil and the coal, leaving the heavier substances .f therein .whichretain a substantially solid state in the carbonized masses discharged from the oven on the receiver adjacent the outlet thereof. The vapors generated in the oven Pass on to the-vapor line for passage to the converting compressor 26 to- 'gether` with other vapors produced from tion the oil is then heated by heat absorbed from `cracked vapors. A'substantial part of this oil, however, is vaporized and these vapors of a temperature of say 500 F. to 600" F. pass through the line 25 into the compressor 26 Where they are subjected to a high degree of compression of say 100' pounds per 7square inch, which raises the temperature of the vapors to approximately from 700o to 850 F., this temperature being controlled by the passage of oil through the jacket 18 of the compressor. The compressor lis operated by the compressor cylinder 11 receiving steam from the line 10 which communicates with the boiler 5. After the vapors -are heated to a cracking temperature inthe-compressor 14 they then pass through the line 27 into the tubes 23 of the heat exchanger 26. Here the vapors heat the charging stock and are themselves largely condensed, constituting converted 10W boiling point oils. Such oils flow through the line 28 into the receiver 29. The unva orized oil in the chamber 20 is Withdrawn t rough the residual line 30 by a pump, or the like, depositing into the tank 31 from Where it is continuously introduced to the amalgamator 1 for the purposes hereinbefore described.

From the foregoing description of the process, it will be seen that I produce solid clean smokeless fuels and liquid motor fuels, that .the manufacture of the solid fuel contributes tothe yield ofliquid fuel, that the production of motor fuel contributes a liquid residuum necessary to the successful manu-V facture of the solid fuel, that Waste or byproduct heat incidental to the production of each product is successfully utilized in the production of the other.

Having thus described my invention, What li claim is: l

1. A process for manufacturing a carbonized solid fuel and converting low boiling point'oils by Aheat generated at a single source, consisting in utilizing a yportion of said heat for subjecting oils to cracking conditions of temperature and pressure, and in employing by-product heat for carbonizing comminuted fuels vto produce ai carbon.- ized residue.

2. A process for manufacturing carbon ized fuels of a solid nature and converting hydrocarbon oils, consistingv ydeveloping heat energyby combustion of a fuel at-a single source, in utilizing said heat for sub'- jecting hydrocarbon vapors to a heat com pression suicient to crack the same, in" employing waste gases for heating lthe solid fuel to remove volatiles therefromand produce a carbonzed. residue.

3. A process for manufacturingsolid carbonaceous fuels and converting hydrocarbon oils by heat energy developed at a single source, consisting in utilizing a part of the. energy for compressing oil vapors to subject said vapors to cracking temperatures and pressures, in mixing hydrocarbon-oil with pulverized coal while in Water suspension, and in utilizing a portion ofthe energy for heating said* Water during the'agitation of the materials. l f

4. A process for manufacturing solid carbonaceous fuels and coverting hydrocarbon oils'by heat energyy developed at a single source, consisting 1n utilizing a part of the energy for compressing oil vapors to subject said vapors tofcracking temperatures and pressures, 1n mixing hydrocarbon oil with pulverized coal while in Water suspension in utilizing a portion. of the energy for heatlng said water during the agitation ofthe materials, and in also utilizing Waste heat of combustion from 'said single source for removing oils from the agglomerated material producing a carbonized mass.

5. A process for manufacturing solid carbonaceous fuels and converting hydrocarbon oils by heat energy developed at a single source, consisting in utilizing a part of the energy for compressing oil vapors to subimI ject said vapors to cracking temperatures and pressures, in mixing hydrocarbon oil With pulverized coal While in Water suspension, in utilizing a portion of the' energy for heating said Water during the agitation of the materials, in also utilizing Waste heat of combustion from said single source for removing oils from the agglomerated material producing a carbonized mass, and in subjecting said removed oils in the form of vapor to said cracking conditions of temperature and pressure.

6. A system of treating hydrocarbon man terials consisting in generating heat at a single source by the combustion of fuel, in utilizing a portion of the heat to convert vhydrocarbon oils by subjecting oil vapors to oil to an amalgamator, in mixing said oil in the amalgamator with coal in water suspension, in utilizing a part of said heat produced at a single source for heating the Water in. said amalgamator, in'discha-rging the agglomerates from said amalgainator, in distilling said agglomerates by heated gases generated at said single source7 and in introducing ,the vapors and gases obtainedffrom Said agglomerates .to said `compressor for conversion. y

7. A process for amalgamating coals and cracking hydrocarbon oils, consisting in mixing hydrocarbon residue with finely pulver` ized coal and water, in introducing charging stock to a heat interchanger Where a portion thereof is vaporized, in subjecting said vapors to a high compression by a heat energy operat-ing a compressor engine, in passing the compressed vapors through the eat interchanger to vaporize portions of the charging stock, in collecting the low boiling point oils thus produced, in Withdrawing residual oil from said heat interchanger, and utilizing the same for agglomeration with the coal, and in maintain- Leeeeaa ing the Water during such agglomeration in a heated "condition -by Waste heat from said COIDPICSSIOD.'

8. A process for amalgamating coals and cracking hydrocarbon oils, consisting in mixing hydrocarbon residue With ized coal and Water, in introducing charging stock to a heat interchanger Where a portion thereof is lvaporized, in subjecting said vapors to a high compression by a heat energy operating a compressor engine, in passing the compressed vapors through the heat interchangKer to va orize portions of the charging stoc in col ecting the low boiling point oils thus produced, in Withdrawing'residual oil from said heat interchanger and utilizing the same for agglomeration with the coal, in maintaining the Water during suchl agglomeration in a heated condition by Waste heat from said compression, in passing the agglomerates to an oven, in vaporizing oil fractions from said agglomerates in said oven, and in passing said fractions to said compressor for conversion therein.

In testimony whereof I aiiix my signature.

' WALTER EDWIN TRENT.

finely pulver- 

